The Groupon logo etched in glass is shown in the lobby of the online coupon company's Chicago offices. New coupon codes come and go every day and many stores always have a coupon of some kind available. It's simply a matter of understanding the basics of how codes work and taking the time to do a little research before placing your order.

We've all seen it while shopping online. That little coupon code box that shows up in the cart or during checkout. It might be labeled promo code, discount code, offer code, source code, gift code, or other variations but, regardless of the name, it always represents a small window of opportunity for extra savings on your order. Use it wisely, and you can maximize your potential savings — but it may take a little know-how to navigate the constantly changing, vast amount of coupon information available on the web.

If you're unfamiliar with how to find and apply the best coupon codes online, don't worry; this article will arm you with the knowledge you need to go from newbie to expert in no time flat. And there are even some tips for you seasoned pros as well!

Couponing 101: Basic Training

First, you need to know what a coupon code is and how to apply it. Coupon codes can give a certain percentage off your order, a fixed dollar amount off, or free or discounted shipping. They can apply to most items a store sells, or only to specific items or categories. Some require a minimum purchase amount.

Stores issue these codes through various channels, such as their email distribution lists, their own website, or through other websites that highlight information on current deals and coupons. Some discounts are applied automatically at checkout without a code, at times only by clicking through a certain link.

How to Read the Codes

A coupon code will be a mix of letters or numbers, usually around 5 to 10 characters in all caps, that will sometimes appear random (ex. FT596RFT) and other times will spell out actual words or portions of words (ex. FREESHIP50). The code itself can sometimes give clues as to what kind of discount it provides. For example, FREESHIP50 would likely be free shipping with a $50 minimum purchase.

How to Apply a Coupon Code

Once you locate a code to use, you can usually apply it to your order by typing it or copying and pasting it into the coupon code box, and then clicking the button to apply it. This box can be found at various stages of checkout, depending on the store you are ordering from.

Some stores will let you apply the code in the shopping cart before proceeding to checkout, while others may not let you apply it until you've reached a certain point in the checkout process. This may be after you enter your shipping and billing address, or even after your credit card information. Just be careful not to accidentally place the order before you've entered the code.

Got it so far? Excellent! Then let's move on to Intermediate Couponing.

Intermediate Couponing

Now that you know the basic elements to using a coupon code online, we'll dig a little deeper into the process. While it's a simple concept — find a code, add an item to your cart, apply the code, and check out — many stores feature complicated checkout systems that can frustrate even seasoned shoppers.

How to Tell If the Discount Was Successfully Applied

Stores vary widely in how they handle promo codes in the checkout process. The best stores are up-front and clear about their codes. They apply the codes right away in the shopping cart, prominently display your discount, and may even provide the exact details of the coupon once you apply it.

If your particular purchase isn't eligible for the discount, some stores will help you find something that is eligible by noting the parameters. Many, but not all, stores will at least display a message explaining if your purchase is invalid or ineligible.

However, many retailers aren't as forthcoming; some stores will have you jump through a few hoops before you find out if the coupon will work for your order. You may have to go through the checkout process and enter all of your information, even your credit card number, before you can see if the coupon is valid. There are also cases where the store will appear to accept a coupon, but will show absolutely no information and no discount, like a coupon black hole.

Troubleshooting a Coupon That Isn't Working

A coupon code might not work for several reasons. Most common are restrictions and exemptions.

Even if a code appears to be general and apply to anything offered on the site, there will typically be at least a few exclusions. Unless specifically stated, coupons won't discount store gift cards or certain brands that are excluded because of manufacturer restrictions. Some coupons will exclude entire categories, such as sale and clearance items, or items with special pricing, such as "Deal of the Day" items. Free shipping coupons may exclude oversized or heavy items. At a few stores, exclusions can be so substantial that it's almost hard to find an item that the code does apply to.

If you see the coupon listed on the store's website, check for a "details" link with fine print that can provide insight into what items are eligible for the discount and what items aren't. These links can be found in a variety of places — on the homepage, on product pages, or in the cart after the code is applied — and it can save a lot of time to review this information to verify if your purchase is eligible before going through the checkout process. Alternatively, try Googling the coupon to find any restrictions.

If the store you are shopping at has a Marketplace, or other sellers listed on their site, coupons may not apply to these items. In most cases, coupons will only apply to items the store sells directly.

A code will also not work if it has already expired. Stores can discontinue codes before the expiration date they provide, or there may not be an exact expiration given, meaning the offer can end at any time.

Enter the Code Correctly

Be sure that you are typing or pasting the coupon code correctly. Most codes are in caps, and some are case-sensitive, so the code might not work if you enter it in lowercase. If you copy-and-paste the code, be sure there are no blank spaces before or after that could prompt an error message. And if the code is email-specific, you will need access to that email account.

Be Sure to Meet the Minimum

Many coupons have a minimum purchase. This means you have to spend a certain amount on eligible items before you can get the discount. The minimum only applies to the actual cost of the items in your order after any instant discounts and does not include extra costs like tax or shipping, when applicable. Again, you can sometimes get clues from the code itself.

Perhaps you found a code like "15OFF100" that, for some reason, appeared to be 15% off with no minimum where you found it, but isn't working for your $50 order. That "100" you see at the end of the code would likely indicate a $100 minimum. You can also try checking the store's website for details or doing an Internet search for the store name and the code to see if you can find more information on the requirements.

Once you've mastered these trouble-shooting skills, then you're ready to move on to Advanced Couponing, in which we teach you how to find coupons on your own.

Advanced Saving: Finding Coupons in the Wild

By now, you're probably feeling pretty clever. You've mastered the basics, and you can easily right your wrongs along the way. Now, you're ready to take it to the next level: sniffing out discounts on the Internet.

A Little Digging Goes a Long Way

Now that we've covered a few coupon basics, you might be wondering where you can find coupon codes. Some stores will list codes right on their website, which is very convenient, but it may not be the best discount available for your particular order. There are also many cases where coupon codes for a store exist, but aren't listed on the store's website at all. This is where a little coupon research comes in handy.

Coupons are easiest to find if you have already decided which store you want to purchase from. If you visit the Coupon Center here at DealNews, you can use the "Find a Store" search box on the right side of the page to type in the store name. You can also use the main search box at the very top of the page. This will take you to the store page, where you can find both coupons and deals for that particular store.

You can also do a general Internet search. We find that it typically suffices to enter the store name and the term "coupons" in Google or your preferred search engine (ex. Best Buy coupons). This should bring up a wide variety of sources for finding coupons for that store.

Perhaps you don't know what store you want to purchase from, but you know the item you want to buy. If you are set on a particular model of TV, for instance, you can search the model number on DealNews to see if any deals are listed for it. Using the model number is a quick way to pinpoint the exact item you are looking for. If you don't see a current deal, you may have to take it a step further and find out which stores are selling the item that you want. Use a search engine like Google to type in the model number, or a combination of brand and model number, to find stores that sell the item. Determine which of the stores you would feel comfortable purchasing from and, from there, you can use the search by store technique to find out if any coupons are available.

Not Finding Any Coupons? Try Signing Up for Emails or Go Social

There are some stores that rarely or never offer coupon codes, so you may not find anything when you search. But, there are still a few other ways to find a discount. Certain stores will send you a coupon right away if you sign up for their emails. Some of the coupons sent to email subscribers may be one-time use codes, which means the code is generated to be unique to that subscriber and can only be used once. At other times, clicking through a link in the store's email is the only way to get the discount. As such, you generally won't see these offers listed on coupon and deal sites.

You can also check all of the store's social media pages. Liking or following a store on social media outlets like Facebook or Twitter may notify you of a coupon. Even if you don't have an account at one of these sites, you may still be able to view the store's page to see a coupon listed exclusively there.

You might even contact the store to ask if they have any coupons available. If you have never ordered from the store before, you are in a particularly good position to do this, as stores are more likely to have discounts to attract new customers. In any case, it doesn't hurt to try.

In the absence of any coupons, you might find that one store's price without a coupon is better than another store's price with one. That TV you've had your eye on may come out at a better price at a store like Walmart or Best Buy without a code, especially considering whether free shipping is offered. You'll want to calculate all of the actual costs involved before making a decision on where to purchase.

Ready for some extra credit? Continue on!

Extra Credit for Coupon Experts

Were you the Hermione Granger of your classroom growing up? Excellent, because now it's time for extra credit that will make you outshine your fellow deal-hunters. It's one thing to find a coupon code on your own, but it's quite another to weigh the pros and cons of a variety of stores and discounts in the quest for the ultimate best price.

Do the Math to Decide Where to Buy

Once you have located coupon codes for a store or a few stores, you may discover that there are a variety of different types of codes available. There may be offers for a certain percentage off, a fixed dollar amount off, or free shipping, and each might have different minimum purchase requirements. Since many stores only allow one coupon code to be applied for each order, you'll want to figure out which coupon is ideal for your particular purchase.

One of the biggest considerations is whether you will be charged shipping. There's nothing like a hefty shipping charge to downgrade an otherwise great deal. For instance, you might be pleased to discover a store is offering a 25% off code with no minimum, perfect for your $30 order. But then a $9.95 shipping charge is tacked on.

Unless you know you're getting free shipping, you'll want to figure out how much shipping will cost you and compare that to the discount another available code would provide, to see which is greater. In the above example, the 25% off coupon would save you $7.50 on a $30 purchase, but if the store also offered a coupon for something like free shipping on $25, that would save even more at $9.95. Of course, coupons that give both a discount and free shipping are even better.

If shipping isn't a factor, choosing a coupon code is simply a matter of figuring out which discount reduces your particular order the most. Generally speaking, smaller orders are more likely to benefit from a fixed discount amount off, such as $5 off $25, than a percentage discount like 10% off, since the percentage amount on a small order can be minimal. As the order gets larger, it is more likely that a percentage discount will be the best.

Spend More, Save More

Spending more on an order can have its advantages. When multiple coupons are available, you'll want to think about whether increasing your order total to meet a minimum for a larger discount might actually work out better for getting maximum value out of your order. Stores often release coupon codes in tiers — or various discount amounts depending on your purchase size — either with the same coupon code or with different codes. As your purchase size goes up, you may become eligible for a larger discount. If you reach a level where a higher discount applies, you might find that you can get more in product value by spending a relatively small amount extra.

As an example, a store might offer a code for 10% off $50 or 20% off $75. Let's say your order amount is right at $50, which would end up at $45 after the 10% discount. However, if you add $25 worth of merchandise to your order to meet the $75 minimum, your order will be $60, which is only $15 more for $25 in extra items.

The same concept can apply to shipping charges. Stores often have ongoing free shipping offers that don't require a code, or they may have a coupon for it. If your order is close to a free shipping minimum, consider what shipping will cost and how much extra you would have to spend to get it free. If shipping is $9.95 and you are $10 away from getting it free, adding another item would be worth doing. If there's a larger difference in what the total will be, and you're not prepared to spend more, then you may have to bite the bullet and pay the shipping charges.

Granted, it isn't always easy to exactly meet a minimum or get very close to it at many stores, due to their pricing structures. And spending more might not be a favorable option for you, if you really don't need additional items. But it's definitely something to consider if your order is hovering near the minimum for a better offer, and you want to get the most bang for your buck.

Stack Up the Savings

While most stores only allow one coupon discount per order, there are some stores that will allow for stacking online codes, which means more than one coupon can be applied. These stores might display several coupon code boxes at checkout, or there may just be one box for applying each code one at a time. If there is only one box, and you still see that box available after applying a code, you might be able to add another one. Stores that have stacking available include Best Buy,Kohl's, Victoria's Secret, Gap Inc. stores (including Banana Republic and Old Navy), Office Depot, and Sears.

What's the catch? There may be heavy restrictions on the type of codes you can combine, and the store may not have more than one coupon available that applies to your order. Combining two percentage or dollar off coupons is less likely to work, but a free shipping code with one of those offers typically will. Regardless, it never hurts to experiment with available codes at any store that allows for stacking, to find out if they are accepted together.

Final Word: Always Use a Coupon

There's plenty of potential to turn your good deal into a great one using codes. If you see that little coupon code box in the cart, make sure that you take that opportunity to save. New coupon codes come and go every day and many stores always have a coupon of some kind available. It's simply a matter of understanding the basics of how codes work and taking the time to do a little research before placing your order.

And, remember, we have an entire staff here at DealNews tracking down deals and coupons for you every day, making it even easier to locate this information quickly.

Sarah Jones is a writer for DealNews, where this article first appeared.

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